1. Field of the Invention
Embodiments of the present invention generally relate to an electrostatic chuck assembly for use in an etching chamber.
2. Description of the Related Art
In the manufacture of integrated circuits, precise control of various process parameters is necessary for achieving consistent results within a substrate, as well as the results that are reproducible from substrate to substrate. During processing, changes in the temperature and temperature gradients across the substrate may be detrimental to material deposition, etch rate, step coverage, feature taper angles, and other parameters of semiconductor devices.
In some processing applications, a substrate is retained to a substrate pedestal by an electrostatic chuck during processing. The electrostatic chuck is coupled to a base of the pedestal by clamps, adhesive, or fasteners. The chuck may be provided with an embedded electric heater, as well as be fluidly coupled to a source of backside heat transfer gas for controlling substrate temperature during processing. However, conventional substrate pedestals have insufficient means for controlling substrate temperature distribution across the diameter of the substrate. The inability to control substrate temperature uniformity has an adverse effect on process uniformity both within a single substrate and between substrates, device yield and overall quality of processed substrates.
Therefore, there is a need in the art for an improved electrostatic chuck assembly.